This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A133109 #13 Mar 07 2022 07:56:17 %S A133109 1,0,3,0,0,4,0,0,0,5,0,0,0,0,7,0,0,0,0,0,8,0,0,0,0,0,0,9,0,0,0,0,0,0, %T A133109 0,11,0,0,0,0,0,0,0,0,12,0,0,0,0,0,0,0,0,0,13,0,0,0,0,0,0,0,0,0,0,15, %U A133109 0,0,0,0,0,0,0,0,0,0,0,16,0,0,0,0,0,0,0,0,0,0,0,0,17 %N A133109 Triangle read by rows, A042965 on the diagonal, 0 elsewhere. %F A133109 A042965: (1, 3, 4, 5, 7, 8, 9, 11, 12, 13, ...) as the diagonal of an infinite lower triangular matrix and the rest zeros. %e A133109 First few rows of the triangle: %e A133109 1; %e A133109 0, 3; %e A133109 0, 0, 4; %e A133109 0, 0, 0, 5; %e A133109 0, 0, 0, 0, 7; %e A133109 ... %o A133109 (PARI) row(n) = vector(n, k, if (k==n, (4*n+1)\3)); \\ _Michel Marcus_, Mar 07 2022 %Y A133109 Cf. A042965, A133110 (binomial transform). %K A133109 nonn,tabl %O A133109 1,3 %A A133109 _Gary W. Adamson_, Sep 12 2007 %E A133109 More terms from _Michel Marcus_, Mar 07 2022